Gastroesophageal reflux disease (GERD) is one of the most common upper-gastrointestinal disorders in the western world, with a prevalence of approximately 360 cases per 100,000 population per year. Approximately 25% of individuals with GERD will eventually have recurrent, progressive disease and are candidates to undergo antireflux surgical procedures for effective long term therapy. Typically an individual afflicted with GERD can control the discomfort associated with the disease by over-the-counter antacids. However, for the more chronic sufferer, prescription drugs are prescribed which can cost as much as $2,000 per year and are one of the most common treatments for GERD. It is estimated that the total direct and indirect costs of GERD prevention and treatment are estimated at $101 billion dollars a year for the United States alone.
GERD is a condition in which acids surge upward from the stomach into the esophagus, the food tube connecting the back of the throat to the stomach. Backflow of acid into the esophagus makes it raw, red and inflamed, producing the condition known as esophagitis; it also causes the painful, burning sensation behind the breastbone known as heartburn. Backflow or reflux of acid can occur when the sphincter or band muscle at the lower end of the esophagus fails to stay closed. This sphincter is called the lower esophageal sphincter (LES). The LES acts as a valve to the stomach, remaining closed until the action of swallowing forces the valve open to allow food to pass from the esophagus to the stomach. Normally the valve closes immediately after swallowing to prevent stomach contents from surging upward. When the LES fails to provide that closure, stomach acids reflux back into the esophagus, causing heartburn.
Various therapies to alleviate the symptoms of esophagitis include loss weight if the individual is overweight, not wearing tight clothing that constricts the stomach and not eating for at least three or four hours before lying down. Other non-drug treatments include avoiding foods that tend to open the LES. These foods include caffeinated beverages, such as coffee, tea and sodas; chocolate; fatty foods and peppermint.
When non-drug treatments are not enough, the individual can take an over-the-counter antacid for the occasional case of heartburn, such as MAALOX.RTM.. Also available are over-the-counter acid blockers like TAGAMET HB.RTM., PEPCID.RTM., AXID AR.RTM. or ZANTAC 75.RTM.. These drugs serve to block the release of acid into an individual's stomach.
Prescription strength versions of the acid blockers available. Additionally, there are other medicines that help empty the stomach of food and reduce the chances of reflux. These medicines are known as pro-kinetic drugs and include PROPULSID.RTM. (cisapride) and REGLAN.RTM. (metoclopramide).
An additional class of medicaments useful in combating esophagitis are known as proton pump inhibitors. These drugs act to block the molecular "pump" that produces acid in the stomach. These drugs include PRILOSEC (omeprazole) and PREVACID (lansoprazole). Proton pump inhibitors are typically used only in severe cases of esophagitis. They are the strongest known medicines available to counter severe symptoms of esophagitis. Typically, a physician will prescribe a combination of a proton pump inhibitor with a pro-kinetic drug, such as for example, the combination of PRILOSEC and PROPULSID.
For that percent of the population whose esophagitis does not fully respond to any prescription treatment, surgery is an option. The general approach for corrective surgery involves creating a new valve or tightening the existing valve. This procedure is known as "fundoplication" and is used to prevent the back flow of stomach acids into the esophagus. Various fundoplication procedures have been developed to correct GERD and are known as Nissen fundoplication, Belsey Mark IV repair, Hill repair and Dor repair. Each surgical procedure has its own unique attributes; however, each requires an invasive surgical procedure, whereby the individual must endure trauma to the thoracic cavity. The individual remains hospitalized after the procedure for about six to ten days.
Each of the surgical procedures were designed with an emphasis on GERD being consistent with a physiologic abnormality secondary to hypertension of the lower esophageal sphincter (LES) and not as the result of an anatomic abnormality. Early on it was not recognized that restoration of normal function between the esophagus and the gastrointestinal tract was a prerequisite of successful antireflux procedures and not just simple restoration of the individual's normal anatomy.
For example, the Nissen fundoplication technique involves enveloping the lower esophagus with the gastric fundus by suturing the anterior and posterior fundal folds about the esophagus. Modifications of this procedure include narrowing of the esophageal hiatus posterior to the esophagus, anchoring of the fundoplication to the preaortic fascia and surgical division of the vegas nerve. The degree of the fundal wrap can be modified to incompletely encircle the esophageal tube to avoid gas float syndrome and has also been modified to include a loose wrap. Similarly, the Belsey Mark IV repair, Hill repair and Dor repair are directed to modifications for encirclement of the esophageal tube by fascia.
Complications of these fundoplication procedures include the inability to belch or vomit, dysphagia, gastric ulcer, impaired gastric emptying and slippage of the repair that may foil the best surgical results. Therefore, the fundoplication procedures have been modified to adjust the length and tension of the wrap, include or exclude esophageal muscle in the sutures and leaving the vagus nerves in or out of the encirclement.
A relatively new fundoplication technique is known as Nissen fundoplication laparoscopy. In contrast to the traditional Nissen fundoplication procedure, which requires a 6 to 10 inch incision and a 6 to 10 day hospital stay with up to 8 weeks of recovery at home, the laparoscopy technique is performed through 4 to 6 tiny openings about the thoracic cavity. One opening is generally at the navel and the others are about the abdomen. Each incision is less than an inch in diameter. A surgeon inserts tubes called trocars into the body and passes a telescope-like instrument, called a laparoscope, which is connected to a camera and a video screen, through a trocar. The surgeon performs the fundoplication, constricting the esophagus much like the traditional Nissen fundoplication procedure. After the surgery is complete there is no large incision and most patients experience less discomfort than a traditional Nissen fundoplication procedure. Patients tend to leave the hospital in two days and can return to work and other activities within a week or two.
An alternative surgical procedure/device described in U.S. Pat. Nos. 3,875,928; 4,271,827; 4,271,828; and 5,006,106, collectively known as the Angelchik antireflux prosthesis (AAP), is also available for treatment of severe GERD. This procedure employs insertion of a donut-shaped prosthesis through an incision made in the abdomen. The prosthesis is placed about the intra-abdominal esophagus. A tape is passed around the esophagus and tied to the prosthesis to pull the prosthesis into position. The tape ends are tied and connected by a hemostasis clip used to secure the tightened ends of the tape. One disadvantage of the AAP is that the device tends to migrate from its original placement. This migration often times causes obstruction of the stomach, and therefore, requires repeated surgery to correct placement of the AAP. Another disadvantage is that the prosthesis cannot be reinflated if a loss of fluid occurs.
Accordingly, an object of this invention is to provide a minimally invasive method and a device for reducing gastroesophageal reflux in a patient.
A further object of this invention is to provide a biocompatible locking device for securing a fold of stomach tissue, such that a valve is created which substantially reduces the flow of gastric juices into the esophagus.
Another object of this invention is to provide a piercing device for retracting a portion of stomach tissue of a patient, such that a valve or flap is created which substantially reduces the flow of gastric juices into the esophagus.
Other general and specific objects of the invention will in part be obvious and will in part appear hereinafter.